JP2011231340A - Initiator/hydroxide and initiator/alkoxide complexes, systems comprising the complexes, and polymerized compositions made therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide initiator systems, such as those used for polymerization of adhesives useful for bonding low surface energy substrates, without prematurely initiating polymerization of monomers present with the complexes or degrading the efficacy of initiators for polymerization of subsequently added monomers.SOLUTION: The initiator systems comprise a complexed initiator and a decomplexer, wherein the complexed initiator comprises at least one of: a complex of a complexing agent comprising at least one hydroxide and an initiator; and a complex of a complexing agent comprising at least one alkoxide and an initiator. The initiator systems are useful for initiating polymerization of at least one monomer to form polymerized compositions. Kits useful for forming the polymerized compositions comprise a polymerizable composition and an initiator component, wherein the initiator component comprises the complexed initiator. Bonding compositions can be prepared by mixing the polymerizable composition of the kit with any of the initiator components.

Description

  The present invention relates generally to complexes of an initiator with a complexing agent containing at least one hydroxide, at least one alkoxide, or mixtures thereof. This complex is useful in an initiator system for polymerizing monomers.

  Systems that initiate polymerization of monomers to make a composition such as an adhesive are known techniques. For example, Skultchi, Patent Document 1, Patent Document 2, and Patent Document 3, describe a binary initiator system that initiates polymerization of an acrylic monomer. The first part of these binary systems typically contains a stable organoborane amine complex and the second part contains an activator. The activator removes the amine group and liberates the organoborane compound, whereby the organoborane compound can initiate the polymerization process. The activator is sometimes referred to as a liberator or decompressor.

  Typical complexes in such systems include organoborane and amine complexes. Although such complexes are useful in many applications, the use of amine complexing agents in such conventional complexes can cause problems. For example, if the complex contains a primary amine, the adhesive prepared from it tends to discolor, such as yellowing. In addition, if the complex-containing composition includes a reactive diluent such as an aziridine functional material described in, for example, US Pat. No. 6,057,049, the diluent is a protic amine (ie, at least one nitrogen atom in the complex). May react prematurely with amines bonded to two hydrogen atoms to decomplex the organoborane initiator early. This phenomenon can initiate the polymerization of monomers present with the complex early or degrade the effectiveness of the initiator for the polymerization of subsequently added monomers.

  In view of these potential problems and the desire to provide alternative formulations, additional complexes are particularly desirable in initiator systems such as those used in the polymerization of adhesives that are useful for bonding low surface energy substrates.

US Pat. No. 5,106,928 US Pat. No. 5,286,821 US Pat. No. 5,310,835 PCT International Publication No. WO 98 / 17,694

  The initiator system of the present invention comprises at least one of a complex of a complexing agent and an initiator containing at least one hydroxide and a complex of a complexing agent and an initiator containing at least one alkoxide. Containing a complexing initiator and a decompressor. Preferably, the initiator comprises an organometallic initiator such as an organoborane initiator.

で表すことができる。式中、Ｒ^１は、１〜約１０個の炭素原子を有するアルキル基である。Ｒ^２およびＲ^３は、同じであっても異なっていてもよく、１〜約１０個の炭素原子を有するアルキル基およびフェニルを含有する基から選択される（すなわち、それらは、独立して、選択される）。「Ｃｘ」は、本発明の錯化剤を表す。「ｖ」の値は、錯体中のアルコキシドおよび／またはヒドロキシドの酸素原子とホウ素原子との有効比を提供するように選択される。 The complex of an organic borane initiator and a complexing agent according to the present invention has the following general formula (I),

Can be expressed as Wherein R ¹ is an alkyl group having 1 to about 10 carbon atoms. R ² and R ³ can be the same or different and are selected from alkyl groups having 1 to about 10 carbon atoms and groups containing phenyl (ie, they are independently Selected). “Cx” represents the complexing agent of the present invention. The value of “v” is selected to provide an effective ratio of oxygen and boron atoms of the alkoxide and / or hydroxide in the complex.

  The initiator system is useful for initiating the polymerization of at least one monomer. To initiate polymerization in such a manner, at least one monomer is provided and blended with the initiator system. The polymerization of at least one monomer can thus be initiated.

In one embodiment, the complexing initiator has the following formula (II):
( ⁽⁻⁾ O—R ⁴ ) _n M ^{(m +)} (II)
The complexing agent represented by these is included. Wherein each R ⁴ is independently selected from hydrogen or an organic group (eg, an alkyl or alkylene group), and M ^{(m +)} is a counter cation (Group IA metal (eg, sodium and potassium) cation) Or a monovalent cation such as onium, or a multivalent cation such as a Group IIA metal (eg, calcium and magnesium) cation), n is an integer greater than zero, and m is greater than zero. A large integer. Preferably n and m are equal. Preferably each R ⁴ is the same in the complexing agent. Particularly preferred complexing agents include complexing agents having a counter cation comprising a cation selected from sodium, potassium, and tetraalkylammonium.

According to another aspect of the present invention, the complexing agent of the present invention is used as part of a kit. In one embodiment, the kit of the present invention comprises
At least one polymerizable monomer, and at least one decompressor;
A polymerizable composition comprising:
A complex of a complexing agent and an initiator containing at least one hydroxide, and a complex of a complexing agent and an initiator containing at least one alkoxide;
A complexing initiator comprising at least one of: an optional diluent;
An initiator component comprising:
including.

  The binding composition can be prepared by mixing the polymerizable composition of the kit with the respective initiator component. The bonding composition can be used, for example, to prepare a substrate that is at least partially coated with the bonding composition, and to prepare a bonded body comprising a first substrate and a second substrate, wherein a polymeric bond The composition adhesively bonds the first and second substrates. The binding composition is particularly useful for coating low surface energy substrates.

  The present invention provides an initiator system that can initiate polymerization. More particularly, the present invention comprises (1) a complexing initiator (eg, an organic borane hydroxide complex, an organic borane alkoxide complex, or a mixture or combination thereof) and (2) a decompressor. An "initiator system" is provided.

  In embodiments of the invention, the initiator system is part of a multi-component kit. Such a kit comprises at least a first part (ie, a polymerizable composition) and a second part (ie, an initiator component) that initiates polymerization of the polymerizable composition. Most preferably, for ease of use, the kit comprises only two parts. The two parts of the kit are conveniently and commercially useful for a total number mixing ratio of 1:10 or less, more preferably 1: 4, 1: 3, 1: 2 or more, so that they can be used easily in a multi-component dispenser. 1: 1 can be formulated immediately. The dispenser is shown in U.S. Pat. Nos. 4,538,920 and 5,082,147 and is traded under the trade name MIXPAC by ConProTec, Inc. (Salem, NH). Each part of the kit is immediately mixed to form a binding composition that immediately polymerizes into a polymer, eg, an adhesive.

  A “polymerizable composition” typically comprises at least one decompressor and at least one polymerizable monomer.

  An “initiator component” typically includes at least one complexing initiator (eg, an organic borane hydroxide complex, an organic borane alkoxide complex, or a mixture or combination thereof) and an optional diluent. When mixed with the polymerizable composition, the decompressor in the polymerizable composition is derived from a complexing agent (eg, a complexing agent containing at least one hydroxide, at least one alkoxide, or a mixture thereof). An initiator (eg, organic borane) can be liberated, thereby initiating polymerization of the monomer (s).

  A “binding composition” is a composition resulting from the mixing of a polymerizable composition according to the present invention and an initiator component. The bonding composition is useful for bonding a wide range of substrates, including substrates derived from polymers, wood, ceramics, concrete, and metals. The bonding composition is particularly useful for bonding low surface energy substrates.

A “low surface energy substrate” is a substrate having a surface energy of less than 45 mJ / m ² , more typically less than 40 mJ / m ² or less than 35 mJ / m ² . Such materials include, for example, polyethylene and polypropylene.

  Other high surface energy polymers that can be usefully associated with the compositions of the present invention include polycarbonate and polymethylmethacrylate. However, the present invention is not limited to these, and compositions that can bond thermoplastics and suitable substrates obtained from wood, ceramics, concrete, prime metals, etc. can be used.

  “Polymerized compositions” (also referred to as polymers) are those in which essentially all of the monomers in the combined composition are polymerized, except in the case of typical non-polymerized amounts that can be distinguished from those of conventional techniques. Composition. The polymerized compositions according to the invention can be used in a wide range of applications including, for example, adhesives, bonding materials, sealants, coatings and injection molded resins. The polymeric composition can also be used as a matrix resin associated with glass, carbon and metal fiber mats used in resin transfer molding. Furthermore, the polymerization composition can be used as an encapsulant and an embedding resin in the production of electric parts, printed circuit boards and the like. One skilled in the art can appreciate a wide variety of other uses for which the polymeric composition is useful.

Initiator Component Complexing Initiator Generally, the complexing initiator of the present invention comprises an initiator and a complexing agent, particularly at least one hydroxide, at least one alkoxide, or a mixture thereof. A complex with a complexing agent. One skilled in the art will readily appreciate that a “complex” is a strongly coordinated salt formed by the association of a Lewis acid (eg, an initiator) and a Lewis base (eg, a hydroxide or alkoxide). Like.

  Any suitable complexing agent containing at least one hydroxide, at least one alkoxide, or a mixture thereof is complexed so long as the complexing agent reacts with the combined decompressor (if any). It can be used as an agent. Furthermore, the complexing agent must be capable of forming a complex with the initiator used in combination.

  Any suitable initiator, or blend thereof, can be used in the present invention, in which case the initiator must be able to form a complex with the complexing agent. Furthermore, the initiator must be able to initiate the polymerization of the monomers used together. Preferably, the initiator is an organometallic initiator.

によって表される。ここで、Ｒ^１は１から約１０の炭素数を有するアルキル基である。Ｒ^２およびＲ^３は同じか又は異なり、１から約１０の炭素数を有するアルキル基およびフェニル含有基より選ばれる（つまり、独立的に選ばれる）。好ましくはＲ^１、Ｒ^２およびＲ^３は１から約５の炭素数を有するアルキル基より独立的に選ばれる。したがって。Ｒ^１、Ｒ^２およびＲ^３はすべて異なるか、又はＲ^１、Ｒ^２およびＲ^３の２つ以上が同じである。Ｒ^１、Ｒ^２およびＲ^３が同じであることが最も好ましい。 According to one aspect of the invention, the initiator is an organoborane initiator. The complex of the organoborane initiator and complexing material of the present invention is represented by the following general formula (I):

Represented by Here, R ¹ is an alkyl group having 1 to about 10 carbon atoms. R ² and R ³ are the same or different and are selected (ie, independently selected) from alkyl groups having 1 to about 10 carbon atoms and phenyl-containing groups. Preferably R ¹ , R ² and R ³ are independently selected from alkyl groups having 1 to about 5 carbon atoms. Therefore. R ¹ , R ² and R ³ are all different or two or more of R ¹ , R ² and R ³ are the same. Most preferably, R ¹ , R ² and R ³ are the same.

R ¹ , R ² and R ³ together with the boron atom (B) to which it is attached form an initiator. Specific organic borane initiators include, for example, trimethylborane, triethylborane, tri-n-propylborane, triisopropylborane, tri-n-butylborane, triisobutylborane, and tri-sec-butylborane.

  “Cx” in formula (I) represents the complexing agent of the present invention. This will be described in detail below.

  The value of “v” is selected to provide an effective ratio of oxygen and boron atoms of the alkoxide and / or hydroxide in the complex. The ratio of oxygen atoms to boron atoms in the alkoxide and / or hydroxide in the complex is broadly about 0.5: 1 to about 4: 1, preferably about 1: 1 to about 2: 1, more preferably about It should be 1: 1 to about 1.5: 1, most preferably about 1: 1.

Complexing agents The following terms are used hereinafter to describe the complexing agents of the present invention in more detail.

  The terms “monovalent organic group” and “polyvalent organic group” mean an organic moiety, in this case the applicable valence for a carbon atom. A monovalent organic group has one applicable value. Therefore, the polyvalent organic group has one or more applicable values.

  An “organic group” is an aliphatic group or a cyclic group. In the context of the present invention, the term “aliphatic group” means a saturated or unsaturated, linear or branched, hydrocarbon group. This term is used to encompass, for example, alkylene, alkenylene, alkynylene, alkyl, alkenyl, and alkynyl groups. The term “alkyl group” means a monovalent, saturated, linear or branched, hydrocarbon group (ie, a methyl, ethyl, isopropyl, t-butyl, heptyl, dodecyl, octadecyl, amyl or 2-ethylhexyl group, etc.). The term “alkylene” means a polyvalent, saturated, linear or branched, hydrocarbon group. The term “alkenyl group” means a monovalent, unsaturated, linear or branched, hydrocarbon group (ie, vinyl group) having one or more carbon-carbon double bonds. The term “alkenylene” means a polyvalent, unsaturated, linear or branched, hydrocarbon group having one or more carbon-carbon double bonds. The term “alkynyl group” means a monovalent, unsaturated, linear or branched, hydrocarbon group having one or more carbon-carbon triple bonds. The term “alkynylene” means a monovalent, linear or branched, hydrocarbon group having one or more carbon-carbon triple bonds.

  The term “cyclic group” or “cyclic structure” means a closed ring hydrocarbon group, which is selected as an alicyclic group, aromatic group or heterocyclic group. The term “alicyclic group” means a cyclic hydrocarbon group having properties in common with those of an alicyclic group. The term “aromatic group” or “allyl group” means a mononuclear aromatic hydrocarbon group or a dinuclear aromatic hydrocarbon group.

  As used herein, an organic or grouped linking group is an internal (ie, not terminal) heteroatom (ie, O, N or S atom) as well as an internal functional group (ie, Carbonyl group).

Cx in formula (I) represents a complexing agent containing at least one hydroxide, at least one alkoxide, or a mixture thereof. Preferably, Cx and the complexing agent of the present invention have the following formula (II):
( ⁽⁻⁾ O—R ⁴ ) _n M ^{(m +)} (II)
It is represented by

Each R ⁴ is independently selected from hydrogen or an organic group, and each of n and m is an integer greater than zero.

Each R ⁴ may be hydrogen in the complexing agent, or each R ⁴ may be an organic group in the complexing agent. When optional R ⁴ is hydrogen, the complexing agent is said to contain at least one hydroxide. When optional R ⁴ is an organic group, the complexing agent is said to contain at least one alkoxide. A preferred alkoxide is an alkoxide in which R ⁴ is an alkyl group or an alkylene group. The complexing agent may also include a mixture of at least one hydroxide and at least one alkoxide.

  Typically n is 1 or 2 and m is 1 or 2. Preferably n and m are the same integer, most preferably 1.

In general, the complexing agent is used in the form of a salt. That is, the complexing agent is stabilized by a suitable counter cation so that the complexing agent can complex the initiator. Accordingly, in Formula II, M ^{(m +)} represents a counter cation that stabilizes the complexing agent.

Any suitable cation or combination thereof can be used for the counter cation of the present invention. As indicated by the superscript “m +”, the cation may be monovalent or multivalent. When “m +” is 1, the cation is monovalent. For example, a monovalent cation of a Group IA metal (lithium, sodium, potassium, etc.) can be used. Other suitable monovalent cations generally include the following formula (III),
(R ⁵ ) _z (X ⁽⁺⁾ ) (III)
The onium which suits is mentioned. Each R ⁵ is independently selected from monovalent organic groups. Accordingly, each R ⁵ in formula (III) may be different, or two or more R ⁵ may be the same. In the formula (III), z represents an integer greater than 1. Typically z is 2, 3, or 4. Typically, X is a Group VA, Group VIA, or Group VIIA metalloid (eg, nitrogen, sulfur, iodine, and phosphorus). Exemplary onium cations include tetraalkylammonium (eg, tetramethylammonium and tetrabutylammonium), triphenylsulfonium, diphenyliodonium, and tetrabutylphosphonium.

  When “m +” is greater than 1, the cation is multivalent. Exemplary multivalent cations include Group IIA metals (eg, calcium and magnesium) or thio.

  Monovalent cations are preferred. Particularly preferred are sodium, potassium, and tetraalkylammonium.

  Certain complexes containing hydroxide are known in the art. For example, Brown, Herbert C., et al. , Hydroboranes, pp. See some of the chemical structures disclosed in 55-56 (1962). However, the use of such complexes in initiator systems has not been reported.

  Hydroxides and alkoxides provide strong bonds to organometallic initiators such as organoboranes, and the resulting complexes have excellent oxidative stability. Thus, the use of complexing agents containing at least one hydroxide, at least one alkoxide, or mixtures thereof is particularly beneficial for the initiator system of the present invention.

  As an advantage, preferred complexes of the present invention are air stable. “Air stability” means that when stored in a capped vessel at room temperature (about 20 ° to about 22 ° C.) and under other environmental conditions (ie, not in a vacuum or in an inert atmosphere), the complex It is meant to be useful as a polymerization initiator for at least about 2 weeks. Preferably, the complex can be easily stored under these conditions for months and up to a year or more.

  When the complex is a crystal material (ie, the complex is solid at room temperature but has a measurable melting point when measured by differential scanning calorimetry), the air stability of the complex is improved. However, the complexes of the present invention are air stable for at least 6 months even when liquid at room temperature. In the examples, liquid complexing agents (ie, complexes having a measurable melting point that is below room temperature when measured by differential scanning calorimetry) and solutions of liquid or solid complexes are preferred. This is because liquids are generally easier to handle and mix at room temperature than solids. One skilled in the art can readily determine whether a complex based on the chosen initiator and complexing agent is liquid or solid at room temperature.

  Particularly preferred “air stable” complexes are non-ignitable. That is, the complex does not spontaneously burn or ignite. Conventional techniques can readily determine whether a complex based on the chosen initiator and amidine complexing agent is non-ignitable. For example, the ignitability test described below in the Examples is one method of determining whether a complex is ignitable.

  Exemplary complexing agents useful for preparing the complexes of the present invention include the following materials: sodium hydroxide, tetrabutylammonium hydroxide, sodium methoxide, and tetrabutylammonium methoxide. Exemplary organoboranes useful for preparing the complexes of the present invention include triethylborane and tributylborane. It should also be noted that blends of different complexes can be used in the initiator system of the present invention.

  The complexes of the present invention can be readily prepared using known techniques. Usually, the complexing agent is slowly stirred and blended with the initiator in an inert atmosphere. It is advisable to cool the mixture as exotherms are frequently observed. When the vapor pressure of the component is high, the reaction temperature is desirably about 70 to 80 ° C. or less. Once the materials are well mixed, the complex may be cooled to room temperature (ie, about 22-25 ° C.). Although it is preferred to keep the complex in a capped vessel in a cool dark place, no special storage conditions are required. The complex is advantageous in that it can be prepared in a solvent if desired, but without an organic solvent that must be removed later.

  The resulting complex is used in an effective amount. That is, it is used in such an amount that it can be easily polymerized to obtain a polymer (preferably an acrylic polymer). According to one aspect of the present invention, when the initiator comprises organoborane, an effective amount of organoborane complex is that of the binding composition minus the weight of filler, non-reactive diluent and other non-reactive components. From about 0.01 wt% boron to about 1.5 wt% boron, more preferably from about 0.01 wt% boron to about 0.60 wt% boron, most preferably about 0.02 wt%, based on the total weight. To about 0.50 wt% boron. If the amount of the organic borane complex is too low, polymerization may be incomplete, or in the case of an adhesive, the composition may have poor adhesion.

  On the other hand, if the amount of organoborane complex is too high, the polymerization may not be able to accommodate the effective mixing and use of the composition that occurs too quickly. A large amount of complex causes generation of a large amount of borane, and in the case of an adhesive, the bond line may be weakened when used as a bonding substrate. The useful rate of polymerization depends in part on the method of applying the composition to the substrate. Thus, it can be prepared to increase the polymerization rate using a high speed automatic industrial adhesive applicator rather than applying the composition with a hand applicator or mixing the composition manually.

Diluent The initiator component also contains a suitable diluent or blend thereof. The diluent may or may not react with the monomers used in the polymerizable composition.

  Preferably the diluent is inert to the complexing agent. That is, preferably the diluent is such that the complexing agent is unable to complex the initiator, or the diluent is chemically modified to affect the desired properties of the composition. Does not substantially contain a portion that reacts with the complexing agent (that is, a portion susceptible to esterification or hydrolysis by the complexing agent).

  Non-reactive diluents include plasticizers known in the art. Reactive diluents include, for example, aziridine functional materials and maleate functional materials. For example, the reactive diluent is PCT International Publication No. WO 98 / 17,694 and US Patent Application No. 09 / 272,152 (“Organic Borane Amine Complex Initiator System Accepted by the Trustee ID No. 54677 USA7A”). And the polymerizable composition ") thereby.

を有する有機化合物である。その炭素原子は選択的に短鎖式アルキル基（つまり、１から約１０の炭素数、好ましくはメチル、エチルまたはプロピルを有する基）に置換され、たとえば、メチル、エチルまたはプロピルアジリジン部分を形成する。 “Aziridine-functional” means at least one aziridine ring or group

It is an organic compound having The carbon atom is optionally substituted with a short chain alkyl group (ie, a group having 1 to about 10 carbon atoms, preferably methyl, ethyl or propyl) to form, for example, a methyl, ethyl or propylaziridine moiety. .

  Examples of useful and commercially available polyaziridines are available under the trade names: CROSSLINKER CX-100 (Zeneca Resins, Wilmington, Mass.), XAMA-2 (EIT, Inc., Lake Wylie, SC), XAMA- 7 (EIT, Inc., Lake Wykie, SC), and MAPO (Tris [1- (2-methyl) aziridinyl] phosphine oxide (Aceto Chemical Corporation, Flushing, NY).

  In use, it is very beneficial for the complex to be supported (dissolved or diluted) by the diluent or by blending two or more different diluents to the initiator component. In general, the diluent should not react with the complex and functions as an extender for the complex. Diluents also generally increase the spontaneous combustion temperature of the initiator component and it is beneficial to increase the non-ignition properties of the initiator component.

  The diluent generally must be dissolved in the monomers included in the polymerizable composition so that the kit parts can be easily mixed. “Soluble” means that at room temperature (ie, about 22 to about 25 ° C.) no evidence of total phase separation is visible to the naked eye. A little warming of the complex and diluent mixture helps to form these two solutions at room temperature (about 22 to about 25 ° C.), but the complex must also be able to dissolve in the diluent. Thus, preferably, when a diluent is used, it is liquid near room temperature (ie, within about 10 ° C. at room temperature) or forms a liquid solution with the complex near that room temperature.

  Diluent is used in an effective amount. Generally, this is an amount of about 50 wt% or less, preferably about 25 wt% or less, more preferably about 10 wt% or less, based on the total weight of the binding composition. However, a substantial amount of the complex (ie, greater than about 15 wt%, sometimes greater than about 40 wt%) can be dissolved in the diluent, thereby binding at commercially useful mixing ratios. It is easy to provide a multi-component kit that can be used.

Polymerizable Composition Decomplexer The term “decomplexer” means a compound capable of liberating an initiator (eg, organoborane) from its complexing agent. This allows the start of the polymerization process. Decomplexers are sometimes called “activators” or “liberators”. These meanings used here have the same meaning.

  Use an appropriate decompressor or blend thereof, such as isocyanates, acids, acid chlorides, sulfonyl chlorides, anhydrides, initiator components and compounds that can liberate any of the foregoing when blended, and mixtures thereof. Can do. Examples of suitable acids include Lewis acids and Bronsted acids. Particularly suitable decompressors include sulfonyl chlorides by the low molecular weight carboxylic acid decompressors, Fujisawa, Imai, Mashara, described by Skultchi et al. (US Pat. Nos. 5,310,835 and 5,106,928). And acid chlorides (Medical and Dental Laboratory Report, Volume 3, page 64 (1969)), a multi-reactive decompressor comprising an isocyanate group as described by Deviny (PCT International Publication No. WO 97 / 07,171) Anhydride Decomplexer described by Deviny (PCT International Publication No. WO 97 / 17,383), Carboxylic Acid Decomplexer described by Deviny et al. (PCT International Publication No. US 98 / 12,296, June 1998) Application, “initiator system and contact by it Compositions), and mixtures thereof. Incorporated by reference herein as all of these publications are references.

  The decompressor is an effective amount (ie, an amount effective to promote polymerization by liberating the initiator from its complexing agent without substantially adversely affecting the desired properties of the final polymerization composition. ). As will be appreciated by those skilled in the art, if too much decompressor is used, the polymerization may proceed too quickly, and in the case of adhesives, the resulting material will have inadequate adhesion to low energy surfaces. May also be shown. However, if only a very small amount of decompressor is used, the polymerization rate may be too slow and the resulting polymer may not have a molecular weight suitable for a particular application. If the polymerization rate is too fast, reducing the amount of decompressor may help to slow the polymerization rate. Thus, within these parameters, the decompressor typically complexed with a hydroxide or alkoxide reactive group (eg, an acid group or an anhydride group) in the decompressor (s). It is provided in an amount such that the ratio of hydroxide group and alkoxide group in the agent (s) is in the range of 0.5: 1.0 to 3.0: 1.0. In order to obtain better performance, preferably the hydroxide or alkoxide reactive groups in the decomplexer (s) and the hydroxide and alkoxide groups in the complexing agent (s) Is in the range of 0.5: 1.0 to 1.0: 1.0, preferably about 1.0: 1.0.

Monomer The initiator system of the present invention can be used to initiate the polymerization of any suitable monomer. Broadly, the polymerizable composition includes at least one ethylenically unsaturated monomer that allows free radical polymerization. There are a vast number of compounds containing ethylenic unsaturation that can be used in the polymerizable composition. Preferably the composition comprises at least one (meso) acrylic monomer, most preferably a methacrylic monomer. Particularly preferred are (meso) acrylic acid derivatives, which contain esters and / or acid amides. Suitable are for example monohydric alcohols which are alcohols having 1 to 12 carbon atoms, such as, for example, methyl (meso) acrylate, methyl (meso) acrylate, butyl (meso) acrylate and ethylhexyl (meso) acrylate). ) Acrylic esters; (Meso) acrylic esters of monohydric alcohols such as ethylene glycol, diethylene glycol, polyethylene glycol and trimethylolpropane; Di- and mono (meso) acrylic esters of glycerol; Triethylene glycol and tetraethylene glycol Di (meso) acrylic acid ester of dipropylene glycol, tripropylene glycol, tetrapropylene glycol and pentapropylene glycol di (meso) acrylic acid ester; Di (meso) acrylic acid ester of a fine propoxylated diphenylolpropane is.

  Basically suitable are polymerizable monomers such as vinyl acetate; vinyl halides such as vinyl chloride, vinyl fluoride, vinyl bromide; styrene; and divinylbenzene. However, these compounds are generally used only in minor amounts in the polymerizable composition.

  Further suitable are acid amides, such as acrylamide; N-methylacrylamide; N-methylmethacrylamide; N, N-dimethylacrylamide, N, N-dimethylmethacrylamide; N-ethylmethacrylamide; N, N-dimethyl. N-N-diethylmethacrylamide; N-butylacrylamide; N-butylmethacrylamide; Nt-butylacrylamide; NN-dibutylmethacrylamide; N- (methacryloyl) piperidine; N- (1,1-dimethyl-3-oxobutyl) -acrylamide; N-1,1,3,3-tetramethylbutylacrylamide; dimethylene-bis- (meso) acrylamide: tetramethylene-bis- (meth) acrylamide; Service methylene-bis-(meso) acrylamide; a and similar compounds; tri (meso) acryloyl diethylenetriamine.

  In general, the emphasis is on monomers having one or two olefinic double bonds in the molecule, in particular heavy bonds on one olefin. The additional use of highly unsaturated components is not excluded, but it should be borne in mind that their presence can lead to embrittlement of the polymer composition.

Additives The binding composition of the present invention further comprises optional additives. In general, such additives are present in the polymerizable composition of the kit. As a result, the polymerizable composition further comprises various optional additives.

  One particularly useful additive is a thickener, such as a medium (about 40,000) molecular weight polybutyl methacrylate, which is generally incorporated in an amount up to about 50% by weight, based on the total weight of the polymerization composition. is there. Thickeners are used to increase the viscosity of the resulting bonding composition to a viscous syrupy softness that is easier to apply.

  Another particularly useful additive is an elastic material. These materials can improve the fracture toughness of the resulting bonding composition. This is beneficial, for example, when bonding rigid, high yield strength materials (ie, metal substrates that do not easily absorb energy mechanically, such as other materials such as flexible polymer substrates). Such additives can generally be incorporated in amounts up to about 50% by weight, based on the total weight of the polymerizable composition.

  The core shell polymer can be added to the polymerizable composition to modify the spreading and flow properties of the binding composition. These improved properties are manifested by a decreasing tendency of the binding composition, leaving undesired “strings” during dispensing from syringe-type applicators and causing deflection or slumping after being applied to a vertical surface. Accordingly, it is desirable to achieve more than about 20% by weight of the core shell polymer additive relative to the total weight of the polymerizable composition in order to achieve an increase in sagging slump resistance. The core shell polymer also improves the fracture toughness of the bonding composition thereby, for example, a metal group that does not mechanically absorb energy mechanically, such as rigid, high yield strength materials (ie other materials such as flexible polymer substrates). This is beneficial when bonding materials.

  Small amounts of inhibitors such as hydroquinone monomethyl ether are used, for example, in polymerizable compositions to prevent or reduce monomer degradation during storage. Inhibitors can be added in amounts that do not significantly affect the polymerization rate or final properties of the polymer. Accordingly, inhibitors are generally useful in amounts of about 100-10,000 ppm based on the total weight of monomers in the polymerizable composition.

  Other possible additives include non-reactive colorants, fillers (ie, carbon black, hollow glass / ceramic beads, silica, titanium dioxide, solid glass / ceramic spheres, and chalk) and the like. The various optional additives are used in any amount, but generally are in amounts that do not significantly adversely affect the polymerization process or desired properties of the polymer.

Binding Composition The parts of the kit (ie, the polymerizable composition and the initiator component) are blended as is normally done when working with such materials. The initiator component is added to the polymerizable composition shortly before the use of the bonding composition is desired.

  Once the kit parts are formulated to form the binding composition, the composition must be used quickly. This is because the useful pot life depends somewhat on the monomer, the amount of initiator component, the temperature at which the coupling takes place, the presence or absence of a crosslinker, and whether a diluent is used. Preferably, it is desirable to maintain the initial bonding temperature below about 40 ° C, preferably below 30 ° C, and most preferably below about 25 ° C to improve bonding. Thus, the bonding process is performed at room temperature (ie, about 22 ° C. to about 25 ° C.).

  The bonding composition is applied to one or both substrates to be bonded, and then the substrates are bonded together at a pressure that drives excess bonding composition out of the bond line. This has the advantage of displacing the binding composition that has been exposed to air and begins to oxidize. In general, the conjugate should be formed in a short time after the bonding composition is applied to the substrate, preferably within about 10 minutes. Typical bond line thickness is about 0.1 to 0.3 millimeters.

  The conjugate cures (ie, polymerizes) to a reasonable green strength, that is, until such a conjugate can be processed within about 2-3 hours. A sufficient bond strength is reached in about 24 hours under environmental conditions. However, when a post-curing process using heat is desired, the process can be performed.

  In one preferred embodiment, the binding composition is coated on a low surface energy substrate. In another preferred embodiment, the bond includes a first substrate and a second substrate (preferably at least one of which is a low surface energy polymeric material) that are adhesively bonded by a layer of a bonding composition according to the present invention. It becomes.

  The invention will be more fully appreciated with reference to the following non-limiting examples. These examples are for illustrative purposes only and are not meant to be limited to the scope of the appended claims. All parts, percentages, ratios, etc. in the examples and the rest of the specification are by weight unless otherwise indicated.

Examples The various trade names and abbreviations used in the examples are defined according to the following list.

Overlap Shear Bond Strength Test Each bond composition (0.2 millimeter (8 mil) -diameter glass bead spacer added to the bond composition) untreated 2.5 cm × 10 cm × 0.3 cm (1 inch × 4 inch × 0) .125 inches) directly onto the test panel and a bare second test panel is bonded onto the first test panel so that the overlap is 1.3 cm x 2.5 cm (0.5 inch x 1 inch) Placed directly against the composition. A clamp was applied to the overlap. The test panels were polytetrafluoroethylene (PTFE), high density polyethylene (HDPE), or polypropylene (PP), as noted in the special examples, all of which were obtained commercially from Cadillac Plastic, Minneapolis, MN. A small amount of the binding composition squeezed out of the overlap was allowed to stand.

  The conjugate was cured at 22 ° C. for at least 48 hours. The clamp was removed and the overlap bonded body was sheared (OLS) tested with a tension tester at a crosshead speed of 1.27 cm / min (0.5 in / min). Overlap shear values were recorded in pounds and converted to pounds per square inch (psi) and megapascals (MPa).

  Preferably, for adequate binding performance, the OLS value is at least 150 psi (1.03 MPa) for PTFE, more preferably at least about 300 psi (4.14 Mpa), and at least about 500 psi (3.45 Mpa) for HDPE. ), More preferably at least about 700 psi (4.83 MPa), and for PP at least about 600 psi (4.14 Mpa), more preferably at least about 800 psi (5.52 MPa). For various utilities, it is preferable if a special adhesive can properly bond at least two different types of low surface energy substrates, and it is more preferable if PTFE, HDPE and PP can all be properly bonded with a special adhesive. PTFE to an OLS value of at least about 300 psi (4.14 MPa) with special adhesive, HDPE to an OLS value of at least about 700 psi (4.83 MPa), and PP to an OLS value of at least about 800 psi (5.52 MPa). It is most preferable if it can be appropriately bonded.

Preparation of organic borane complexes Examples 1-3
A complex of sodium hydroxide, sodium methoxide and potassium tert-butoxide and triethylborane was prepared by combining equimolar amounts of complexing agent and triethylborane under nitrogen atmosphere without external temperature control. . These complexes were prepared as an aqueous solution, a methanol solution, and a tetrahydrofuran solution, respectively. The aqueous solution of sodium hydroxide and triethylborane initially formed separated phases and became homogeneous after mixing for several hours at room temperature. The amount of each component and the type of complexing agent are listed in Table 1.

Ignition test:
The ignitability of each organic borane complex (Examples 1-3) was tested by applying treated 0.05 ml aliquots to 1 "x 1" paper towel pieces in air to produce treated paper towels. If the treated paper towel self-ignites (ie, spontaneous combustion) within 1 minute, the composition is considered ignitable. If the treated paper towel does not self-ignite after 10 minutes, the composition is considered non-ignitable. Table 2 lists the results of examining whether each composition is ignitable according to the above test.

¹ H-NMR spectroscopy (proton nuclear magnetic resonance spectroscopy)
The ¹ H-NMR chemical shift in CDCl _{3 of} the methylene group adjacent to boron in the sodium methoxide triethylborane complex further demonstrated the strong binding of the organoborane complexes useful in the present invention. The ¹ H-NMR shift of the methylene group adjacent to boron in the organoborane complexes useful in the present invention appears below about δ0.5. In triethylborane itself, the ¹ H-NMR shift of the methylene group adjacent to boron is about δ1.2. When the composition prepared in Example 2 was tested by ¹ H-NMR spectroscopy, the results shown in Table 3 were obtained.

Preparation of binding composition Example 4
Initiator Component The triethylborane complex of Example 1 (1.78 grams of solution) (TEB-NaOH) was dissolved in 1.55 grams of CROSSLINKER CX-100. Bubbles in the composition were lifted to escape.

Polymerizable composition The polymerizable composition comprises 39.00 grams of methyl methacrylate (MMA), 28,000 grams of butyl acrylate (BA), 5.35 grams of methacrylic acid (MAA), and 30.00 grams of poly ( MMA-co-EA). Bubbles were removed from the composition by briefly stirring under vacuum.

Binding Composition The polymerizable composition and initiator component were packaged in a MIXPAC SYSTEM 50 applicator. The large cylinder of the applicator held the polymerizable composition and the small cylinder held the initiator component. The two parts were compounded by coextrusion through a 10 centimeter (4 inch) long 17 stage static mixing nozzle (part number MX4-0-17-5, commercially available from ConProTec, Salem, NH). Test materials were prepared in this way and tested by the lap shear bond strength test. However, in this case, a steel wire spacer (0.2 millimeter (8 mil) diameter) was inserted into the wet adhesive between the first and second untreated test panels before clamping. The results of the lap shear test for Example 4 are listed in Table 4.

Example 5
Initiator Component Aqueous triethylborane complex prepared in Example 1 (6.57 grams of solution) (TEB-NaOH), 11.05 grams of CX-100, 1.42 grams of CAB-O-SIL TS 720, and An initiator component was prepared by combining 0.96 grams of P25.

Polymerizable Composition 19.85 grams of methyl methacrylate (MAA), 9.75 grams of butyl acrylate (BA), 2.40 grams of methacrylic acid (MAA), 13.50 grams of BLENDEX 360, and 4.55 grams A polymerizable composition was prepared by heating a slurry containing ELVACITE 2010 of 70 ° C. for 3 hours. The resulting dispersion was cooled and then vigorously sheared with a Laboratory Dispersator serrated blade commercially available from Premier Mill Corporation; Reading, PA. Air bubbles were removed from the composition by briefly stirring under reduced pressure.

  The polymerizable composition and the initiator component were packaged and evaluated as described in Example 4. The results of tests conducted according to the lap shear bond strength test are listed in Table 5.

  Various modifications and alterations of this invention will become apparent to those skilled in the art without departing from the scope and spirit of this invention. It should be understood that the present invention is not limited to the exemplary embodiments described herein.

Claims (18)

A complex of a complexing agent and an initiator containing at least one hydroxide, and a complex of a complexing agent and an initiator containing at least one alkoxide;
A complexing initiator comprising at least one of
With a decompressor,
An initiator system comprising:   The initiator system of claim 1, wherein the initiator comprises an organometallic initiator.   The initiator system of claim 1, wherein the initiator comprises an organoborane initiator.   The initiator system of claim 1, wherein the complexing initiator comprises a complex of an initiator and a complexing agent containing at least one hydroxide.   The initiator system of claim 1, wherein the complexing initiator comprises a complex of an initiator and a complexing agent containing at least one alkoxide. The complexing initiator is represented by the following formula (II):
( ⁽⁻⁾ O—R ⁴ ) _n M ^{(m +)} (II)
(Where
R ⁴ is independently selected from hydrogen or an organic group;
M ^{(m +)} represents a counter cation,
n is an integer greater than zero, and m is an integer greater than zero. The initiator system of claim 1 comprising a complexing agent represented by:   7. The initiator system according to claim 6, wherein n and m are equal. 7. The initiator system according to claim 6, wherein each R ⁴ is independently an alkyl group or an alkylene group. The initiator system of claim 6 wherein each R ⁴ is hydrogen. The initiator system of claim 6 wherein M ^{(m +)} comprises a monovalent cation. The initiator system of claim 10, wherein M ^{(m +)} comprises onium. 7. The initiator system of claim 6, wherein M ^{(m +)} is selected from a sodium cation, a potassium cation, a tetraalkylammonium cation, and combinations thereof. At least one polymerizable monomer, and at least one decompressor;
A polymerizable composition comprising:
A complex of a complexing agent and an initiator containing at least one hydroxide, and a complex of a complexing agent and an initiator containing at least one alkoxide;
A complexing initiator comprising at least one of: an optional diluent;
An initiator component comprising:
A kit comprising:   14. A binding composition comprising the polymerizable composition of the kit of claim 13 mixed with the respective initiator component of the kit of claim 13.   A substrate that is at least partially coated with the binding composition of claim 14.   16. A substrate according to claim 15 comprising a low surface energy substrate. A first substrate;
A second substrate;
The polymerized binding composition of claim 14 wherein the first substrate and the second substrate are adhesively bonded and integrated.
A bonded article comprising: A method for initiating polymerization of at least one monomer comprising:
Providing at least one monomer;
Blending the at least one monomer with the initiator system of claim 1;
Initiating polymerization of the at least one monomer;
Comprising a method.